STK SOLIS is a commercial plug-in to the Analytical Graphics, Inc (AGI) Systems ToolKit (STK™) mission analysis software, providing integrated end-to-end spacecraft simulation. Running ASI’s MAX Flight Software and ODySSy, STK SOLIS provides simulation capabilities of all major spacecraft subsystems.

Initial Conditions, Mode Definitions, Mass Properties, Disturbance Modeling
Attitude Control
  • Actuator Models
  • Momentum Control
  • Perfect, PID, & Custom Controllers
Actuator Models
Momentum Control
Perfect, PID, & Custom Controllers
Attitude Determiniation/Nav
  • Sensor Models
  • Attitude Initialization/Acquisition
  • Perfect, Fixed Gain, Kalman Filter
  • Orbit Determination
  • Battery Charge Control
  • Fixed & Articulated Solar Arrays
  • Perfect, PID, & Custom Controllers
Attitude Determiniation/Nav
  • Sensor Models
  • Attitude Initialization/Acquisition
  • Perfect, Fixed Gain, Kalman Filter
  • Orbit Determination

Graphical-interface simplifies configuration of spacecraft subsystems, simulation setup, and analysis:

  • “Wizards” are provided to simplify the configuration of complex systems
  • Variable levels of subsystem fidelity for rapid or detailed analysis
  • Flight code and command/telemetry databases are dynamically configured and can be targeted for specified computing-platform
  • Supports rapid analysis for design tradeoffs, capability assessments, and constraint evaluation

Fully-integrated with the DevTool to support custom algorithms and simulation components that interact with the core spacecraft

Running actual flight software built on ASI’s MAX Flight Software framework:

  • Commanding the simulation is identical to commanding an actual spacecraft
    • A Command/Telemetry bridge process provides capability to interact with user-specific custom databases
  • Leverages full-featured sequencing language; permitting features such as fault monitoring and response
  • Generation of sequences is simplified through the use of the Sequence Editor and Target Planner

Evaluation of spacecraft and mission design requires substantial modeling of the space and ground environments. Leveraging the capabilities of STK; SOLIS provides a spacecraft simulation with unmatched:

  • Visual representation
  • Situational awareness
  • Mission planning
  • Environment modeling
  • Multi-object interaction
  • System observability

This combination empowers users to rapidly develop, analyze, and test solutions to many complex problems.

Flight software configured from STK SOLIS can be targeted for actual flight avionics with limited effort

  • The same tools that accelerated the design and analysis cycle now yield similar benefits throughout AI&T and operations
  • As a consistent partner from concept through operations; STK SOLIS ensures seamless transition across program phases and a true “test like you fly” approach from the beginning



  • Attitude Disturbance Modeling
    • Magnetic dipole, gravity gradient
  • Attitude Determination Modeling
    • Sun sensors, horizon sensors, rate sensors, magnetometers, star trackers
    • Perfect attitude determination, fixed-gain filter, Kalman filter
  • Attitude Control Modeling
    • Reaction wheels, magnetic torquers, thrusters
    • Perfect control, PIID control, phase-plane control
  • Mode Control / Guidance
    • Orbit determination, ephemeris propagation
    • Idle, Rate Damp, Inertial Hold
    • Inertial Point, Sun Track, Nadir Track, Velocity Track, Mag Field Track, Spotlight
    • Rotisserie, Nadir Scan, Lat/Lon Scan
    • Eigen-Axis Slew, Direct-To Slew (Phase-Plane Control)
  • Power/Thermal Modeling
    • Distance-dependent solar flux, central body infrared, albedo
    • Finite element thermal; absorptivity, emissivity, conductivity, shunt
    • Solar panel size, efficiency, articulation, temperature dependency
    • Battery capacity, charge/discharge regulation
    • Dynamic spacecraft loads; payload power, comm system power, reaction wheel power
  • Payload/Communications/Data Recorder Modeling
    • Off, On, Standby
    • Define multiple payload modes; power consumption, data collection
    • Transmitters, receivers, transceivers; data rates, overhead, power consumption
    • Data recorder size, current state
    • Command/telemetry availability when ground stations are visible.
  • Flight Emulation
    • Mission sequence modeling, real-time commanding, telemetry


Spacecraft Design

  • System/Mission Requirements
    • Requirements definition, feasibility studies, component selection
  • Conceptual Design
    • Analyze various system concepts to determine which can meet mission requirements
  • Preliminary Design
    • Variations of conceptual designs are analyzed and refined
    • Define subsystem and component level specifications
  • Critical Design
    • Final design verification of subsystem models and components
  • Risk Reduction and IV&V
    • Independent validation and sensitivity/margin analysis

Spacecraft Operations

  • Training and analysis tool for ground operators and mission analysts

For more information on SOLIS contact